Tray sealing machines with protective covers are known from WO 2011/154743, specifically shown in FIGS. 1 and 2, and from EP 1996470 B1, specifically FIG. 1, wherein the protective covers are provided on the machine frame to be upwardly pivotable about a horizontal axis. The area covered can thereby be made accessible from a front and rear operator side for cleaning or maintenance work; this requires respectively pivotable protective covers on the front and rear operator side. An access from above is here not possible.
Thermoforming machines are known from practice and EP 1772384 A1, specifically shown in FIG. 3; these comprise protective covers that are not mechanically connected to the machine frame, but the presence of the protective cover is monitored by the machine control by means of sensors. These protective hoods are removable and are deposited on the floor or otherwise at a remote place to make the covered area accessible on all sides for cleaning or maintenance work. Due to the arbitrary removal of the protective hoods and the haphazard deposition by the operating personnel the protective hoods may get damaged, and an accurate repositioning and the subsequent checking by sensors may be aggravated or even prevented. As a possible consequence, the thermoforming machine can no longer be started. Another problem is the risk of soiling on protective hoods placed e.g. on the floor. For reasons of hygiene this is above all critical or not admissible in the food sector.